The secret of bowel bacteria

Scientists have so far found many bacteria that produce electricity in various exotic environments, such as mines or lakes. Now, for the first time, they discovered what lay under their noses. Hundreds of bacterial species within the human intestine also produce electrical current.

Some of these electro-generating bacteria in the body are pathogenic, such as those that cause food poisoning by listeria and miscarriages, those responsible for gangrene, certain enterococci and streptococci and others.

Other bacteria are probiotic (“good”) and some, such as lactobacilli, help fermentations eg. yoghurt and cheese. Researchers at the University of California-Berkeley, led by Molecular and Cell Biology Professor Dan Portney, who published the publication in the journal Nature, said the discovery is good news for scientists trying to develop live microbial batteries.

Such innovative “green” bioenergy technologies may in the future, for example, to generate electricity from bacteria in waste management units.

“We have so far escaped that so many bacteria interacting with humans are electrogenic, either as pathogens or as probiotics or involved in the fermentation of human products. This discovery will help us learn a lot about how these bacteria infect us or help us have a healthy bowel, “Portney said.

Bacteria generate electricity for the same reason people breathe oxygen: to remove electrons produced during metabolism and to support energy production in their bodies. While animals and plants carry their electrons to oxygen in their cell mitochondria, bacteria living in an oxygen-free environment such as the human intestine use a completely different electron transfer mechanism.

In non-cell geological environments, bacteria “breathe” e.g. iron or manganese, that is, transporting their electrons (their electricity) to a metal through appropriate geochemical reactions. For this reason, some scientists connect an electrode to these bacteria and in this way they can create a live battery that generates electricity.

The current generated by microorganisms within the body reaches 500 microamps. Bacteria in the intestine produce, according to the researchers, about as much electricity as the known electrogenic bacteria found in the rocks (about 100,000 electrons per second).